IOWA CITY — Just after the postgame interview time, Carl Davis put his hands on the wall, bent a knee and tried to stretch a calf. It was nearly an hour after the game and the Iowa defensive tackle was still feeling the strain.

Hey, kind of like everyone Iowa.

Northern Iowa (0-1) made the Hawkeyes (1-0) sweat this one out. In the end, Iowa's 85 scholarships beat UNI's 63 (the difference between FBS and FCS schools). Iowa's offense answered some questions, the defense has to answer a few, but, finally on Saturday, Iowa put the squeeze on UNI, 31-23, before 66,805 at Kinnick Stadium.

Everyone Iowa should be enjoying a nice, cleansing stretch. That was strain.

“This is pretty much 60 minutes of turmoil in your stomach, and I might as well get used to it because that's usually how it feels,” Iowa coach Kirk Ferentz said.

There was stomach turmoil. The Panthers pulled within one point after kicker Michael Schmadeke's third field goal, a 38-yarder that made it 24-23 Iowa early in the fourth quarter.

The Hawkeyes peeled another player off the player tree in their answer. Quarterback Jake Rudock connected with freshman wide receiver Derrick Willies for a 46-yard gain to UNI's 8. Rudock hooked up with wide receiver Damond Powell for a 12-yard TD and the Hawkeyes had their breathing room with 6:50 left in the game.

From there, Iowa ground it out. The defense pressured UNI quarterback Sawyer Kollmorgen and the desperation led to cornerback Greg Mabin's first career interception.

“I think the guys amped it up there in that fourth quarter after struggling,” Ferentz said. “It wasn't much fun there for a while.”

The game was odd on several fronts for the Hawkeyes. They never found a comfort zone in really anything.

Rudock completed 31 of 41 for 250 yards and two TDs. He hit career highs for completions and yards. Rudock was particularly solid in the second quarter after the Panthers took a 10-7 lead. He led a 17-play, 79-yard drive that ended with running back Mark Weisman's 1-yard TD plunge. Then, he directed a two-minute drill to perfection, setting up kicker Marshall Koehn's 40-yard field goal with one second left for a 17-13 halftime lead.

“The two-minute drill, I thought we did a good job taking what they gave us,” said Rudock, who became the first Iowa QB to complete 30-plus passes in a game since James Vandenberg's 31 against Pitt in 2011. “It didn't all come in one chunk.”

Rudock put up career numbers, but Iowa's best and most productive offensive player might've been UNI's penalties. The Panthers were called for 16 penalties for 128 yards. All five of Iowa's scoring drives were either nudged along or greatly helped by Panther penalties. There's no pinpointing the most crushing penalty, but UNI did stop Iowa on a third-and-goal from the 3-yard line before linebacker Max Busher was called for a holding penalty.

“You're more mad like you go get beat by someone in our league because you know you did it to yourself instead of the other way,” UNI coach Mark Farley said. “We have to learn from our mistakes because we had all the penalties, that's the first thing we need to correct.”

Another sign of discomfort zone for Iowa's offense was the fact that wide receiver Tevaun Smith led the team lead with 35 yards rushing. He did that on a reverse before making a SportsCenter-level one-handed catch for a 6-yard TD and a 24-13 lead in the third quarter.

Weisman finished with 34 yards on 10 carries. Running back by committee found no rhythm.

“Yeah, I didn't see that coming,” wide receiver Kevonte Martin-Manley said when asked about Smith leading Iowa's rush attack.

The obvious malfunction with the defense was covering UNI running back David Johnson out of the backfield. He beat linebacker Quinton Alston for two long gains, including a 70-yard TD reception that made it 24-20 Iowa midway through the third quarter.

Johnson finished with five catches for 203 receiving yards. Kollmorgen finished 17 of 37 for 380 yards, two TDs and two interceptions. Iowa's defense racked up six sacks and 13 tackles for loss, the most they've had in a game in at least the last six years.

“You freak out a little bit,” Alston said. “You've got to keep calm and move on to the next play.”

That sounds like the famous T-shirt. “Stomach turmoil” doesn't sound like a really fun T-shirt.